Q: My question has to do with the pressure gauges for our fire sprinkler system. We just had some out of date pressure gauges replaced by a new sprinkler contractor. They removed the 3 1/2 inch gauges and replaced them with 2 inch gauges. Upon further inspection I noticed that the gauges had no UL or FM listing. They have on the back a CRN aka Canadian Registration Number. Can this type of gauge be used?
A: The Canadian Registration Number (CRN) is a number issued by each province or territory of Canada for the design of a boiler, pressure vessel or fitting. The CRN identifies the design has been accepted and registered for use in that province or territory. You are in Florida, so there is no requirement in the USA for a CRN. According to NFPA 13-2010, the standard on the installation of sprinkler systems, section 188.8.131.52 says the pressure gauges must be listed and must have a maximum limit not less than twice the normal system working pressure at the point where installed. It is apparent that the Canadian Registration Number is not the same as a listing from an independent testing laboratory, so I would say the gauges that were installed at your facility would not be acceptable.